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582 lines
17 KiB
C
582 lines
17 KiB
C
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// SPDX-License-Identifier: GPL-2.0
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/*
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* HCTR2 length-preserving encryption mode
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*
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* Copyright 2021 Google LLC
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*/
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/*
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* HCTR2 is a length-preserving encryption mode that is efficient on
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* processors with instructions to accelerate AES and carryless
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* multiplication, e.g. x86 processors with AES-NI and CLMUL, and ARM
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* processors with the ARMv8 crypto extensions.
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*
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* For more details, see the paper: "Length-preserving encryption with HCTR2"
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* (https://eprint.iacr.org/2021/1441.pdf)
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*/
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#include <crypto/internal/cipher.h>
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#include <crypto/internal/hash.h>
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#include <crypto/internal/skcipher.h>
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#include <crypto/polyval.h>
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#include <crypto/scatterwalk.h>
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#include <linux/module.h>
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#define BLOCKCIPHER_BLOCK_SIZE 16
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/*
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* The specification allows variable-length tweaks, but Linux's crypto API
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* currently only allows algorithms to support a single length. The "natural"
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* tweak length for HCTR2 is 16, since that fits into one POLYVAL block for
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* the best performance. But longer tweaks are useful for fscrypt, to avoid
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* needing to derive per-file keys. So instead we use two blocks, or 32 bytes.
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*/
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#define TWEAK_SIZE 32
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struct hctr2_instance_ctx {
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struct crypto_cipher_spawn blockcipher_spawn;
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struct crypto_skcipher_spawn xctr_spawn;
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struct crypto_shash_spawn polyval_spawn;
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};
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struct hctr2_tfm_ctx {
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struct crypto_cipher *blockcipher;
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struct crypto_skcipher *xctr;
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struct crypto_shash *polyval;
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u8 L[BLOCKCIPHER_BLOCK_SIZE];
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int hashed_tweak_offset;
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/*
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* This struct is allocated with extra space for two exported hash
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* states. Since the hash state size is not known at compile-time, we
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* can't add these to the struct directly.
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*
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* hashed_tweaklen_divisible;
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* hashed_tweaklen_remainder;
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*/
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};
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struct hctr2_request_ctx {
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u8 first_block[BLOCKCIPHER_BLOCK_SIZE];
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u8 xctr_iv[BLOCKCIPHER_BLOCK_SIZE];
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struct scatterlist *bulk_part_dst;
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struct scatterlist *bulk_part_src;
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struct scatterlist sg_src[2];
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struct scatterlist sg_dst[2];
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/*
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* Sub-request sizes are unknown at compile-time, so they need to go
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* after the members with known sizes.
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*/
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union {
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struct shash_desc hash_desc;
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struct skcipher_request xctr_req;
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} u;
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/*
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* This struct is allocated with extra space for one exported hash
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* state. Since the hash state size is not known at compile-time, we
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* can't add it to the struct directly.
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*
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* hashed_tweak;
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*/
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};
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static inline u8 *hctr2_hashed_tweaklen(const struct hctr2_tfm_ctx *tctx,
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bool has_remainder)
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{
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u8 *p = (u8 *)tctx + sizeof(*tctx);
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if (has_remainder) /* For messages not a multiple of block length */
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p += crypto_shash_statesize(tctx->polyval);
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return p;
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}
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static inline u8 *hctr2_hashed_tweak(const struct hctr2_tfm_ctx *tctx,
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struct hctr2_request_ctx *rctx)
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{
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return (u8 *)rctx + tctx->hashed_tweak_offset;
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}
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/*
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* The input data for each HCTR2 hash step begins with a 16-byte block that
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* contains the tweak length and a flag that indicates whether the input is evenly
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* divisible into blocks. Since this implementation only supports one tweak
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* length, we precompute the two hash states resulting from hashing the two
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* possible values of this initial block. This reduces by one block the amount of
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* data that needs to be hashed for each encryption/decryption
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*
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* These precomputed hashes are stored in hctr2_tfm_ctx.
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*/
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static int hctr2_hash_tweaklen(struct hctr2_tfm_ctx *tctx, bool has_remainder)
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{
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SHASH_DESC_ON_STACK(shash, tfm->polyval);
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__le64 tweak_length_block[2];
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int err;
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shash->tfm = tctx->polyval;
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memset(tweak_length_block, 0, sizeof(tweak_length_block));
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tweak_length_block[0] = cpu_to_le64(TWEAK_SIZE * 8 * 2 + 2 + has_remainder);
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err = crypto_shash_init(shash);
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if (err)
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return err;
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err = crypto_shash_update(shash, (u8 *)tweak_length_block,
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POLYVAL_BLOCK_SIZE);
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if (err)
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return err;
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return crypto_shash_export(shash, hctr2_hashed_tweaklen(tctx, has_remainder));
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}
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static int hctr2_setkey(struct crypto_skcipher *tfm, const u8 *key,
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unsigned int keylen)
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{
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struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
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u8 hbar[BLOCKCIPHER_BLOCK_SIZE];
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int err;
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crypto_cipher_clear_flags(tctx->blockcipher, CRYPTO_TFM_REQ_MASK);
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crypto_cipher_set_flags(tctx->blockcipher,
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crypto_skcipher_get_flags(tfm) &
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CRYPTO_TFM_REQ_MASK);
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err = crypto_cipher_setkey(tctx->blockcipher, key, keylen);
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if (err)
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return err;
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crypto_skcipher_clear_flags(tctx->xctr, CRYPTO_TFM_REQ_MASK);
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crypto_skcipher_set_flags(tctx->xctr,
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crypto_skcipher_get_flags(tfm) &
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CRYPTO_TFM_REQ_MASK);
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err = crypto_skcipher_setkey(tctx->xctr, key, keylen);
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if (err)
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return err;
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memset(hbar, 0, sizeof(hbar));
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crypto_cipher_encrypt_one(tctx->blockcipher, hbar, hbar);
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memset(tctx->L, 0, sizeof(tctx->L));
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tctx->L[0] = 0x01;
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crypto_cipher_encrypt_one(tctx->blockcipher, tctx->L, tctx->L);
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crypto_shash_clear_flags(tctx->polyval, CRYPTO_TFM_REQ_MASK);
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crypto_shash_set_flags(tctx->polyval, crypto_skcipher_get_flags(tfm) &
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CRYPTO_TFM_REQ_MASK);
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err = crypto_shash_setkey(tctx->polyval, hbar, BLOCKCIPHER_BLOCK_SIZE);
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if (err)
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return err;
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memzero_explicit(hbar, sizeof(hbar));
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return hctr2_hash_tweaklen(tctx, true) ?: hctr2_hash_tweaklen(tctx, false);
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}
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static int hctr2_hash_tweak(struct skcipher_request *req)
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{
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struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
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const struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
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struct hctr2_request_ctx *rctx = skcipher_request_ctx(req);
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struct shash_desc *hash_desc = &rctx->u.hash_desc;
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int err;
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bool has_remainder = req->cryptlen % POLYVAL_BLOCK_SIZE;
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hash_desc->tfm = tctx->polyval;
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err = crypto_shash_import(hash_desc, hctr2_hashed_tweaklen(tctx, has_remainder));
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if (err)
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return err;
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err = crypto_shash_update(hash_desc, req->iv, TWEAK_SIZE);
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if (err)
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return err;
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// Store the hashed tweak, since we need it when computing both
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// H(T || N) and H(T || V).
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return crypto_shash_export(hash_desc, hctr2_hashed_tweak(tctx, rctx));
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}
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static int hctr2_hash_message(struct skcipher_request *req,
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struct scatterlist *sgl,
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u8 digest[POLYVAL_DIGEST_SIZE])
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{
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static const u8 padding[BLOCKCIPHER_BLOCK_SIZE] = { 0x1 };
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struct hctr2_request_ctx *rctx = skcipher_request_ctx(req);
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struct shash_desc *hash_desc = &rctx->u.hash_desc;
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const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
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struct sg_mapping_iter miter;
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unsigned int remainder = bulk_len % BLOCKCIPHER_BLOCK_SIZE;
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int i;
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int err = 0;
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int n = 0;
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sg_miter_start(&miter, sgl, sg_nents(sgl),
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SG_MITER_FROM_SG | SG_MITER_ATOMIC);
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for (i = 0; i < bulk_len; i += n) {
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sg_miter_next(&miter);
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n = min_t(unsigned int, miter.length, bulk_len - i);
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err = crypto_shash_update(hash_desc, miter.addr, n);
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if (err)
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break;
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}
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sg_miter_stop(&miter);
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if (err)
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return err;
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if (remainder) {
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err = crypto_shash_update(hash_desc, padding,
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BLOCKCIPHER_BLOCK_SIZE - remainder);
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if (err)
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return err;
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}
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return crypto_shash_final(hash_desc, digest);
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}
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static int hctr2_finish(struct skcipher_request *req)
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{
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struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
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const struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
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struct hctr2_request_ctx *rctx = skcipher_request_ctx(req);
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u8 digest[POLYVAL_DIGEST_SIZE];
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struct shash_desc *hash_desc = &rctx->u.hash_desc;
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int err;
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// U = UU ^ H(T || V)
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// or M = MM ^ H(T || N)
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hash_desc->tfm = tctx->polyval;
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err = crypto_shash_import(hash_desc, hctr2_hashed_tweak(tctx, rctx));
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if (err)
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return err;
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err = hctr2_hash_message(req, rctx->bulk_part_dst, digest);
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if (err)
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return err;
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crypto_xor(rctx->first_block, digest, BLOCKCIPHER_BLOCK_SIZE);
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// Copy U (or M) into dst scatterlist
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scatterwalk_map_and_copy(rctx->first_block, req->dst,
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0, BLOCKCIPHER_BLOCK_SIZE, 1);
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return 0;
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}
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static void hctr2_xctr_done(struct crypto_async_request *areq,
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int err)
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{
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struct skcipher_request *req = areq->data;
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if (!err)
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err = hctr2_finish(req);
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skcipher_request_complete(req, err);
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}
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static int hctr2_crypt(struct skcipher_request *req, bool enc)
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{
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struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
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const struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
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struct hctr2_request_ctx *rctx = skcipher_request_ctx(req);
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u8 digest[POLYVAL_DIGEST_SIZE];
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int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
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int err;
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// Requests must be at least one block
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if (req->cryptlen < BLOCKCIPHER_BLOCK_SIZE)
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return -EINVAL;
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// Copy M (or U) into a temporary buffer
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scatterwalk_map_and_copy(rctx->first_block, req->src,
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0, BLOCKCIPHER_BLOCK_SIZE, 0);
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// Create scatterlists for N and V
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rctx->bulk_part_src = scatterwalk_ffwd(rctx->sg_src, req->src,
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BLOCKCIPHER_BLOCK_SIZE);
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rctx->bulk_part_dst = scatterwalk_ffwd(rctx->sg_dst, req->dst,
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BLOCKCIPHER_BLOCK_SIZE);
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// MM = M ^ H(T || N)
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// or UU = U ^ H(T || V)
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err = hctr2_hash_tweak(req);
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if (err)
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return err;
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err = hctr2_hash_message(req, rctx->bulk_part_src, digest);
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if (err)
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return err;
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crypto_xor(digest, rctx->first_block, BLOCKCIPHER_BLOCK_SIZE);
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// UU = E(MM)
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// or MM = D(UU)
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if (enc)
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crypto_cipher_encrypt_one(tctx->blockcipher, rctx->first_block,
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digest);
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else
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crypto_cipher_decrypt_one(tctx->blockcipher, rctx->first_block,
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digest);
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// S = MM ^ UU ^ L
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crypto_xor(digest, rctx->first_block, BLOCKCIPHER_BLOCK_SIZE);
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crypto_xor_cpy(rctx->xctr_iv, digest, tctx->L, BLOCKCIPHER_BLOCK_SIZE);
|
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// V = XCTR(S, N)
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// or N = XCTR(S, V)
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skcipher_request_set_tfm(&rctx->u.xctr_req, tctx->xctr);
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skcipher_request_set_crypt(&rctx->u.xctr_req, rctx->bulk_part_src,
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rctx->bulk_part_dst, bulk_len,
|
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rctx->xctr_iv);
|
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skcipher_request_set_callback(&rctx->u.xctr_req,
|
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req->base.flags,
|
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hctr2_xctr_done, req);
|
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|
return crypto_skcipher_encrypt(&rctx->u.xctr_req) ?:
|
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|
hctr2_finish(req);
|
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|
}
|
||
|
|
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|
static int hctr2_encrypt(struct skcipher_request *req)
|
||
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{
|
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return hctr2_crypt(req, true);
|
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|
}
|
||
|
|
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static int hctr2_decrypt(struct skcipher_request *req)
|
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|
{
|
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|
return hctr2_crypt(req, false);
|
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|
}
|
||
|
|
||
|
static int hctr2_init_tfm(struct crypto_skcipher *tfm)
|
||
|
{
|
||
|
struct skcipher_instance *inst = skcipher_alg_instance(tfm);
|
||
|
struct hctr2_instance_ctx *ictx = skcipher_instance_ctx(inst);
|
||
|
struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
|
||
|
struct crypto_skcipher *xctr;
|
||
|
struct crypto_cipher *blockcipher;
|
||
|
struct crypto_shash *polyval;
|
||
|
unsigned int subreq_size;
|
||
|
int err;
|
||
|
|
||
|
xctr = crypto_spawn_skcipher(&ictx->xctr_spawn);
|
||
|
if (IS_ERR(xctr))
|
||
|
return PTR_ERR(xctr);
|
||
|
|
||
|
blockcipher = crypto_spawn_cipher(&ictx->blockcipher_spawn);
|
||
|
if (IS_ERR(blockcipher)) {
|
||
|
err = PTR_ERR(blockcipher);
|
||
|
goto err_free_xctr;
|
||
|
}
|
||
|
|
||
|
polyval = crypto_spawn_shash(&ictx->polyval_spawn);
|
||
|
if (IS_ERR(polyval)) {
|
||
|
err = PTR_ERR(polyval);
|
||
|
goto err_free_blockcipher;
|
||
|
}
|
||
|
|
||
|
tctx->xctr = xctr;
|
||
|
tctx->blockcipher = blockcipher;
|
||
|
tctx->polyval = polyval;
|
||
|
|
||
|
BUILD_BUG_ON(offsetofend(struct hctr2_request_ctx, u) !=
|
||
|
sizeof(struct hctr2_request_ctx));
|
||
|
subreq_size = max(sizeof_field(struct hctr2_request_ctx, u.hash_desc) +
|
||
|
crypto_shash_descsize(polyval),
|
||
|
sizeof_field(struct hctr2_request_ctx, u.xctr_req) +
|
||
|
crypto_skcipher_reqsize(xctr));
|
||
|
|
||
|
tctx->hashed_tweak_offset = offsetof(struct hctr2_request_ctx, u) +
|
||
|
subreq_size;
|
||
|
crypto_skcipher_set_reqsize(tfm, tctx->hashed_tweak_offset +
|
||
|
crypto_shash_statesize(polyval));
|
||
|
return 0;
|
||
|
|
||
|
err_free_blockcipher:
|
||
|
crypto_free_cipher(blockcipher);
|
||
|
err_free_xctr:
|
||
|
crypto_free_skcipher(xctr);
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
static void hctr2_exit_tfm(struct crypto_skcipher *tfm)
|
||
|
{
|
||
|
struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
|
||
|
|
||
|
crypto_free_cipher(tctx->blockcipher);
|
||
|
crypto_free_skcipher(tctx->xctr);
|
||
|
crypto_free_shash(tctx->polyval);
|
||
|
}
|
||
|
|
||
|
static void hctr2_free_instance(struct skcipher_instance *inst)
|
||
|
{
|
||
|
struct hctr2_instance_ctx *ictx = skcipher_instance_ctx(inst);
|
||
|
|
||
|
crypto_drop_cipher(&ictx->blockcipher_spawn);
|
||
|
crypto_drop_skcipher(&ictx->xctr_spawn);
|
||
|
crypto_drop_shash(&ictx->polyval_spawn);
|
||
|
kfree(inst);
|
||
|
}
|
||
|
|
||
|
static int hctr2_create_common(struct crypto_template *tmpl,
|
||
|
struct rtattr **tb,
|
||
|
const char *xctr_name,
|
||
|
const char *polyval_name)
|
||
|
{
|
||
|
u32 mask;
|
||
|
struct skcipher_instance *inst;
|
||
|
struct hctr2_instance_ctx *ictx;
|
||
|
struct skcipher_alg *xctr_alg;
|
||
|
struct crypto_alg *blockcipher_alg;
|
||
|
struct shash_alg *polyval_alg;
|
||
|
char blockcipher_name[CRYPTO_MAX_ALG_NAME];
|
||
|
int len;
|
||
|
int err;
|
||
|
|
||
|
err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
|
||
|
if (err)
|
||
|
return err;
|
||
|
|
||
|
inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
|
||
|
if (!inst)
|
||
|
return -ENOMEM;
|
||
|
ictx = skcipher_instance_ctx(inst);
|
||
|
|
||
|
/* Stream cipher, xctr(block_cipher) */
|
||
|
err = crypto_grab_skcipher(&ictx->xctr_spawn,
|
||
|
skcipher_crypto_instance(inst),
|
||
|
xctr_name, 0, mask);
|
||
|
if (err)
|
||
|
goto err_free_inst;
|
||
|
xctr_alg = crypto_spawn_skcipher_alg(&ictx->xctr_spawn);
|
||
|
|
||
|
err = -EINVAL;
|
||
|
if (strncmp(xctr_alg->base.cra_name, "xctr(", 5))
|
||
|
goto err_free_inst;
|
||
|
len = strscpy(blockcipher_name, xctr_alg->base.cra_name + 5,
|
||
|
sizeof(blockcipher_name));
|
||
|
if (len < 1)
|
||
|
goto err_free_inst;
|
||
|
if (blockcipher_name[len - 1] != ')')
|
||
|
goto err_free_inst;
|
||
|
blockcipher_name[len - 1] = 0;
|
||
|
|
||
|
/* Block cipher, e.g. "aes" */
|
||
|
err = crypto_grab_cipher(&ictx->blockcipher_spawn,
|
||
|
skcipher_crypto_instance(inst),
|
||
|
blockcipher_name, 0, mask);
|
||
|
if (err)
|
||
|
goto err_free_inst;
|
||
|
blockcipher_alg = crypto_spawn_cipher_alg(&ictx->blockcipher_spawn);
|
||
|
|
||
|
/* Require blocksize of 16 bytes */
|
||
|
err = -EINVAL;
|
||
|
if (blockcipher_alg->cra_blocksize != BLOCKCIPHER_BLOCK_SIZE)
|
||
|
goto err_free_inst;
|
||
|
|
||
|
/* Polyval ε-∆U hash function */
|
||
|
err = crypto_grab_shash(&ictx->polyval_spawn,
|
||
|
skcipher_crypto_instance(inst),
|
||
|
polyval_name, 0, mask);
|
||
|
if (err)
|
||
|
goto err_free_inst;
|
||
|
polyval_alg = crypto_spawn_shash_alg(&ictx->polyval_spawn);
|
||
|
|
||
|
/* Ensure Polyval is being used */
|
||
|
err = -EINVAL;
|
||
|
if (strcmp(polyval_alg->base.cra_name, "polyval") != 0)
|
||
|
goto err_free_inst;
|
||
|
|
||
|
/* Instance fields */
|
||
|
|
||
|
err = -ENAMETOOLONG;
|
||
|
if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "hctr2(%s)",
|
||
|
blockcipher_alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
|
||
|
goto err_free_inst;
|
||
|
if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
|
||
|
"hctr2_base(%s,%s)",
|
||
|
xctr_alg->base.cra_driver_name,
|
||
|
polyval_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
|
||
|
goto err_free_inst;
|
||
|
|
||
|
inst->alg.base.cra_blocksize = BLOCKCIPHER_BLOCK_SIZE;
|
||
|
inst->alg.base.cra_ctxsize = sizeof(struct hctr2_tfm_ctx) +
|
||
|
polyval_alg->statesize * 2;
|
||
|
inst->alg.base.cra_alignmask = xctr_alg->base.cra_alignmask |
|
||
|
polyval_alg->base.cra_alignmask;
|
||
|
/*
|
||
|
* The hash function is called twice, so it is weighted higher than the
|
||
|
* xctr and blockcipher.
|
||
|
*/
|
||
|
inst->alg.base.cra_priority = (2 * xctr_alg->base.cra_priority +
|
||
|
4 * polyval_alg->base.cra_priority +
|
||
|
blockcipher_alg->cra_priority) / 7;
|
||
|
|
||
|
inst->alg.setkey = hctr2_setkey;
|
||
|
inst->alg.encrypt = hctr2_encrypt;
|
||
|
inst->alg.decrypt = hctr2_decrypt;
|
||
|
inst->alg.init = hctr2_init_tfm;
|
||
|
inst->alg.exit = hctr2_exit_tfm;
|
||
|
inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(xctr_alg);
|
||
|
inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(xctr_alg);
|
||
|
inst->alg.ivsize = TWEAK_SIZE;
|
||
|
|
||
|
inst->free = hctr2_free_instance;
|
||
|
|
||
|
err = skcipher_register_instance(tmpl, inst);
|
||
|
if (err) {
|
||
|
err_free_inst:
|
||
|
hctr2_free_instance(inst);
|
||
|
}
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
static int hctr2_create_base(struct crypto_template *tmpl, struct rtattr **tb)
|
||
|
{
|
||
|
const char *xctr_name;
|
||
|
const char *polyval_name;
|
||
|
|
||
|
xctr_name = crypto_attr_alg_name(tb[1]);
|
||
|
if (IS_ERR(xctr_name))
|
||
|
return PTR_ERR(xctr_name);
|
||
|
|
||
|
polyval_name = crypto_attr_alg_name(tb[2]);
|
||
|
if (IS_ERR(polyval_name))
|
||
|
return PTR_ERR(polyval_name);
|
||
|
|
||
|
return hctr2_create_common(tmpl, tb, xctr_name, polyval_name);
|
||
|
}
|
||
|
|
||
|
static int hctr2_create(struct crypto_template *tmpl, struct rtattr **tb)
|
||
|
{
|
||
|
const char *blockcipher_name;
|
||
|
char xctr_name[CRYPTO_MAX_ALG_NAME];
|
||
|
|
||
|
blockcipher_name = crypto_attr_alg_name(tb[1]);
|
||
|
if (IS_ERR(blockcipher_name))
|
||
|
return PTR_ERR(blockcipher_name);
|
||
|
|
||
|
if (snprintf(xctr_name, CRYPTO_MAX_ALG_NAME, "xctr(%s)",
|
||
|
blockcipher_name) >= CRYPTO_MAX_ALG_NAME)
|
||
|
return -ENAMETOOLONG;
|
||
|
|
||
|
return hctr2_create_common(tmpl, tb, xctr_name, "polyval");
|
||
|
}
|
||
|
|
||
|
static struct crypto_template hctr2_tmpls[] = {
|
||
|
{
|
||
|
/* hctr2_base(xctr_name, polyval_name) */
|
||
|
.name = "hctr2_base",
|
||
|
.create = hctr2_create_base,
|
||
|
.module = THIS_MODULE,
|
||
|
}, {
|
||
|
/* hctr2(blockcipher_name) */
|
||
|
.name = "hctr2",
|
||
|
.create = hctr2_create,
|
||
|
.module = THIS_MODULE,
|
||
|
}
|
||
|
};
|
||
|
|
||
|
static int __init hctr2_module_init(void)
|
||
|
{
|
||
|
return crypto_register_templates(hctr2_tmpls, ARRAY_SIZE(hctr2_tmpls));
|
||
|
}
|
||
|
|
||
|
static void __exit hctr2_module_exit(void)
|
||
|
{
|
||
|
return crypto_unregister_templates(hctr2_tmpls,
|
||
|
ARRAY_SIZE(hctr2_tmpls));
|
||
|
}
|
||
|
|
||
|
subsys_initcall(hctr2_module_init);
|
||
|
module_exit(hctr2_module_exit);
|
||
|
|
||
|
MODULE_DESCRIPTION("HCTR2 length-preserving encryption mode");
|
||
|
MODULE_LICENSE("GPL v2");
|
||
|
MODULE_ALIAS_CRYPTO("hctr2");
|
||
|
MODULE_IMPORT_NS(CRYPTO_INTERNAL);
|